Introduce AccessibilityFocusRing.

chrome/browser/chromeos/ui/accessibility_focus_ring.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/chromeos/ui/accessibility_focus_ring.h"
+
+namespace chromeos {
+
+// static
+AccessibilityFocusRing AccessibilityFocusRing::CreateWithRect(
+    const gfx::Rect& bounds, int margin) {
+  gfx::Rect top(bounds.x(), bounds.y(),
+                bounds.width(), bounds.height() / 4);
+  gfx::Rect body(bounds.x(), top.bottom(),
+                 bounds.width(), bounds.height() / 2);
+  gfx::Rect bottom(bounds.x(), body.bottom(),
+                   bounds.width(), bounds.bottom() - body.bottom());
+  return CreateWithParagraphShape(top, body, bottom, margin);
+}
+
+// static
+AccessibilityFocusRing AccessibilityFocusRing::CreateWithParagraphShape(
+    const gfx::Rect& orig_top_line,
+    const gfx::Rect& orig_body,
+    const gfx::Rect& orig_bottom_line,
+    int margin) {
+  gfx::Rect top = orig_top_line;
+  gfx::Rect middle = orig_body;
+  gfx::Rect bottom = orig_bottom_line;
+
+  if (top.x() <= middle.x() + 2 * margin) {
+    top.set_width(top.width() + top.x() - middle.x());
+    top.set_x(middle.x());
+  }
+  if (top.right() >= middle.right() - 2 * margin) {
+    top.set_width(middle.right() - top.x());
+  }
+
+  if (bottom.x() <= middle.x() + 2 * margin) {
+    bottom.set_width(bottom.width() + bottom.x() - middle.x());
+    bottom.set_x(middle.x());
+  }
+  if (bottom.right() >= middle.right() - 2 * margin) {
+    bottom.set_width(middle.right() - bottom.x());
+  }
+
+  AccessibilityFocusRing ring;
+  ring.points[0] = gfx::Point(top.x(), top.bottom() - margin);
+  ring.points[1] = gfx::Point(top.x(), top.y() + margin);
+  ring.points[2] = gfx::Point(top.x(), top.y());
+  ring.points[3] = gfx::Point(top.x() + margin, top.y());
+  ring.points[4] = gfx::Point(top.right() - margin, top.y());
+  ring.points[5] = gfx::Point(top.right(), top.y());
+  ring.points[6] = gfx::Point(top.right(), top.y() + margin);
+  ring.points[7] = gfx::Point(top.right(), top.bottom() - margin);
+  ring.points[8] = gfx::Point(top.right(), top.bottom());
+  if (top.right() < middle.right()) {
+    ring.points[9] = gfx::Point(top.right() + margin, middle.y());
+    ring.points[10] = gfx::Point(middle.right() - margin, middle.y());
+  } else {
+    ring.points[9] = gfx::Point(top.right(), middle.y());
+    ring.points[10] = gfx::Point(middle.right(), middle.y());
+  }
+  ring.points[11] = gfx::Point(middle.right(), middle.y());
+  ring.points[12] = gfx::Point(middle.right(), middle.y() + margin);
+  ring.points[13] = gfx::Point(middle.right(), middle.bottom() - margin);
+  ring.points[14] = gfx::Point(middle.right(), middle.bottom());
+  if (bottom.right() < middle.right()) {
+    ring.points[15] = gfx::Point(middle.right() - margin, bottom.y());
+    ring.points[16] = gfx::Point(bottom.right() + margin, bottom.y());
+  } else {
+    ring.points[15] = gfx::Point(middle.right(), bottom.y());
+    ring.points[16] = gfx::Point(bottom.right(), bottom.y());
+  }
+  ring.points[17] = gfx::Point(bottom.right(), bottom.y());
+  ring.points[18] = gfx::Point(bottom.right(), bottom.y() + margin);
+  ring.points[19] = gfx::Point(bottom.right(), bottom.bottom() - margin);
+  ring.points[20] = gfx::Point(bottom.right(), bottom.bottom());
+  ring.points[21] = gfx::Point(bottom.right() - margin, bottom.bottom());
+  ring.points[22] = gfx::Point(bottom.x() + margin, bottom.bottom());
+  ring.points[23] = gfx::Point(bottom.x(), bottom.bottom());
+  ring.points[24] = gfx::Point(bottom.x(), bottom.bottom() - margin);
+  ring.points[25] = gfx::Point(bottom.x(), bottom.y() + margin);
+  ring.points[26] = gfx::Point(bottom.x(), bottom.y());
+  if (bottom.x() > middle.x()) {
+    ring.points[27] = gfx::Point(bottom.x() - margin, bottom.y());
+    ring.points[28] = gfx::Point(middle.x() + margin, middle.bottom());
+  } else {
+    ring.points[27] = gfx::Point(bottom.x(), bottom.y());
+    ring.points[28] = gfx::Point(middle.x(), middle.bottom());
+  }
+  ring.points[29] = gfx::Point(middle.x(), middle.bottom());
+  ring.points[30] = gfx::Point(middle.x(), middle.bottom() - margin);
+  ring.points[31] = gfx::Point(middle.x(), middle.y() + margin);
+  ring.points[32] = gfx::Point(middle.x(), middle.y());
+  if (top.x() > middle.x()) {
+    ring.points[33] = gfx::Point(middle.x() + margin, middle.y());
+    ring.points[34] = gfx::Point(top.x() - margin, top.bottom());
+  } else {
+    ring.points[33] = gfx::Point(middle.x(), middle.y());
+    ring.points[34] = gfx::Point(top.x(), top.bottom());
+  }
+  ring.points[35] = gfx::Point(top.x(), top.bottom());
+
+  return ring;
+}
+
+gfx::Rect AccessibilityFocusRing::GetBounds() const {
+  gfx::Point top_left = points[0];
+  gfx::Point bottom_right = points[0];
+  for (size_t i = 1; i < 36; i++) {
+    top_left.SetToMin(points[i]);
+    bottom_right.SetToMax(points[i]);
+  }
+  return gfx::Rect(top_left, gfx::Size(bottom_right.x() - top_left.x(),
+                                       bottom_right.y() - top_left.y()));
+}
+
+}  // namespace chromeos